Harrow.



C. O. HALD.

HARROW.

APPLICATION HLED NOV. 24. mm.

1,295,484. Patented Feb. 25, 1919.

TTO/PNE Y Y n era PATEN OFFICE.

HARROW.

Specification of Letters Patent.

Patented Feb. 25, 1919.

Application filed November 24-, 1917. Serial No. 203,837.

This invention relates to improvements in harrows and its object is toproduce a harrow of simple construction that is' eflicient in operation.With the foregoing and other objects in view the invention consists inthe combination and arrangement of parts to be hereinafter fullydescribed, pointed out in the appendedclaims and illustrated in theaccompanying drawings which form a part of this specificationand inwhich Figure 1 is a view of my improved harrow in front elevation.

Fig. 2 is a perspective view of one form of tooth employed. p

Fig. 3 is a sectional view through Fig. 2.

Like reference characters denote corresponding parts throughout.

The reference numeral 1 denotes the longi tudinal and 2 the transversebars. The teeth 3 extend through said bars and are carried by the same.To the bars 1 I secure the draft bars 4; to which the draft chains, notshown, are secured. At the ends of the harrow frame, or throughout theframe if preferred, I provide a type of tooth adapted to ride overstones and obstructions generally. A block 6 isformed with a solidportion 7 that carries a tooth 8, the threaded shank 9 of which risesabove said portion 7 to pass through the bars 1, 2 and a pin 10 alsocarried by the block portion 7 is adapted to fit into a small recess ineach bar 1 to revent a pivotal movement of the said block.

The block 6 is formed with a hollow slotted portion 11 which rises at anangle above the block portion 7 and in said hollow portion 11 anexpansion coil spring 12 is arranged which abuts against the head 13 ofthe movable tooth 14:. Should the free end of the tooth 14 encounter anobstruction, when the harrow is moving forward, the tooth head willcompress the spring 12 and in doing so it will ride over the upwardlyinclined base of the hollow portion of the block and so lift the tooth14 high enough to carry it over the average obstruction without dangerof damage to the tooth. The spring also acts as a shock absorber andprotects the tooth from breakage by sudden impact with a non-flexiblesubstance.

What is claimed is 1. In a harrow, a frame, boxes comprising solid andhollow portions, the hollow portions being pitched at an angle to thesolid portions, expansion springs disposed in the hollow box portions,teeth movably carried by the hollow box portions, said teeth beingyieldingly retained in a predetermined position with relation to saidhollow box portions through contact with said springs, and means forsecuring the solid box portions to said frame.

2. In a harrow, a frame, boxes comprising solid and hollow portions, thehollow box portions being pitched at an angle to the solid portions,expansion springs disposed in the hollow box portions, teeth movablycarried by the hollow box portions, said teeth being yieldingly retainedin a predetermined position with relation to said hollow box portionsthrough contact with said springs, teeth carried by said solid boxportions and formed with threaded shanks to engage said frame, and pinscarried by said solid portions for engagement with said frame.

3. In a harrow, hollow slotted boxes secured to the frame thereof, saidboxes being disposed at an oblique angle to the harrow frame, expansionsprings carried in said boxes, and teeth movably carried by said boxes,said teeth being yieldingly retained in a predetermined position withrelation to said boxes through contact with said springs.

In testimony that I claim the foregoing as my own I have hereto aflixedmy signature inthe presence oftwo subscribing witnesses.

CHRISTIAN OLUF I-IALD.

Witnesses:

L. K. LARSON, OLUT HEGGE.

Copies of this patent may he obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. G.

